We had a lot of legacy cruft involving string types in our Subversion

code (the backends in particular). Some of this was due to some

guesswork in string handling, and some due to just being legacy and

Subvertpy having changed over time.
Our Subvertpy code in particular had some old methods of coercing string

types (the B() wrapper), which stood out from the rest of our codebase

and wasn't very compatible with Python 3 (and could potentially cause

problems when encountering some Unicode characters). Subvertpy itself

these days is fairly flexible in terms of string types on all supported

Python versions, which means that some of the coercing work we were

doing wasn't even necessary.
For Subvertpy, we're no longer using B() wrapper, and we're not

worrying about string types for parameters that are flexible. For the

results of some operations, though, we're now converting to the correct

types.
PySVN was mostly fine, but there were some Python 2-isms that didn't

work in Python 3, causing crashes or tripping other string checks that

have recently been introduced. These have been updated to use/convert to

the right string types.

All Subversion unit tests pass on PySVN and Subvertpy on Python 2.7

and 3.7.